1. Field of the Invention
This invention relates to a perpendicular magnetic head which performs recording and reproduction of information magnetized perpendicularly with respect to the recording surface of a magnetic recording medium.
2. Description of Prior Arts
In recent years, there has been adopted a recording system utilizing perpendicular magnetization. The system serves as a high density magnetic recording system capable of rendering a diamagnetic field of the recording magnetization to be zero, and, further, as a system for improving the recording density in the magnetic recording.
Unlike a longitudinal recording system which has so far been used most generally and which leaves in the recording surface of the magnetic recording medium a magnetization direction which is substantially parallel with the recording surface, the perpendicular magnetization system is so constructed that the orientation of the residual magnetization becomes substantially perpendicular to the surface of the recording medium. According to such structure, as the recording wavelength becomes shorter, the diamagnetic field to the recording magnetization is reduced to make it possible to stabilize the magnetization, whereby high density recording becomes practicable. More concretely, while the longitudinal recording system which has so far been used widely is only capable of recording and reproducing information with a wavelength of 1 .mu.m or so with respect to the running direction of the recording medium, the perpendicular recording system has succeeded in recording and reproducing information with a wavelength as short as 0.3 .mu.m, and has potential for a higher recording density.
Such conventional perpendicular magnetic recording system will be outlined hereinbelow with reference to its actual construction, function, and various problems inherent therein, in reference to the accompanying drawing.